The invention relates to a separator that includes a centrifuge drum with a vertical rotational axis and a feed line for a product to be centrifugally processed. The separator further includes a drive spindle for the drum that is rotatably mounted in a housing by a bearing arrangement and which is elastically supported on a machine frame. Also included is an electric motor which has a stator and a rotor which is aligned with the drive spindle.
Such separators, which are also suitable for industrial use, such as in continuous operation, are known from the prior art.
The known systems include designs in which the drum, the drive spindle and the electric drive motor are rigidly connected to form one structural unit which is then elastically supported in its entirety on a machine frame. Examples of such prior art are disclosed by FR 1.287.551, DE 1 057 979 and DE 43 14 440 C1. It is disadvantageous that such arrangements are relatively large in size and large masses have to be moved in terms of oscillation.
DE 2005 001 539 U1 presents a separator having a wrap around gear mechanism.
Further background also includes CH 329 841, CH 107 681, U.S. Pat. No. 2,040,351 and WO 99/42 221 A1.
The present disclosure relates to a compact separator which can be manufactured cost-effectively and in which the motor area can be divided from the bearing area or bearing space.
The present disclosure relates to a separator that includes a centrifuge drum having a vertical rotational axis and a feed line to feed a product to be centrifugally processed. Further included is a drive spindle to drive the centrifugal drum, which drive spindle is rotatably mounted in a housing by a bearing device and which is supported on a machine frame by an elastic support. Also included is a drive device including an electric drive motor having a stator and a motor rotor which is aligned with the drive spindle. The stator is rigidly connected to the machine frame. The motor rotor, the drive spindle, the centrifuge drum, and the housing form a unit which is supported on the machine frame by the elastic support and which unit oscillates during an operation of the separator. The bearing device is arranged between the motor and the drum.
According to the just-mentioned disclosure, the stator is rigidly connected to the machine frame. The motor rotor, the drive spindle, the centrifuge drum and the housing form a unit which is elastically supported on the machine frame and oscillates during operation. The entire bearing device, for the drive spindle, is arranged between the motor and the drum.
Since the stator is directly supported on the machine frame, and the motor rotor is seated directly on the drive spindle, a particularly compact, vertical design can be implemented using only a small number of components.
The arrangement of the bearing device between the motor and the drum permits an axially short design in which the bearing area and the motor are, or can be, structurally separated from one another. The lubrication of the bearing device can be separated from the motor, which is not the case in arrangements in which the motor is arranged between a neck bearing and a footstep bearing. Nevertheless, the motor can still be supported with its stator directly in the machine frame.
DE 596 402 A, DE 545 120 A and GB 368 247 disclose the measure that the stator is supported directly on the machine frame and the motor rotor is seated directly on the drive spindle. However, since the bearings are arranged axially in the motor area or since bearings are located axially on each side of the motor, the motor area cannot be separated from the bearings. The present disclosure provides an advantage in that the motor area can be separated from the bearings.
The oscillating unit is configured in such a way that the center of rotation, for example, of the precision movement, is at the axial and radial center point of the rotor or motor rotor and does not differ far from the center point. This is done in such a way that the motor rotor can no longer rotate freely in the machine housing. This ensures that, for example, during operation, contact cannot occur between the motor rotor and the drum.
As a result of this measure, the separator drive is configured in such a way that the relative conditions between the stator and the motor rotor, which were brought about by the design according to the present disclosure, are reduced to a minimum. Thus, it becomes possible to arrange the motor rotor in the oscillating system and to arrange the stator in or on the non-oscillating machine frame, which permits a particularly compact and cost-effective design. Furthermore, the oscillating mass of the system is kept small, since only the rotor of the motor is involved in it.
The coordination, in terms of oscillation, is configured “supercritically” so that the oscillating system composed of the drum, drive spindle and motor rotor is mounted and configured with a low natural resonant frequency in the ultra sockets, wherein the natural resonant frequency is relatively far below the customary operating rotational speed range of the drum. An advantage is that during operation the system runs in a relatively stable way with only small deflections since the resonant frequency is already run through when the system starts up at a relatively low rotational speed of the drum.
The motor rotor is connected directly to the drive spindle in a rotationally fixed fashion or is embodied in one piece therewith. Elements which lengthen the design, such as a clutch, can be dispensed with in this way. In addition, the manufacturing costs are also reduced further.
Other aspects of the present disclosure will become apparent from the following descriptions when considered in conjunction with the accompanying drawings.